Mutagenesis

[Joanne D. Andreadis]

I've been trying rather unsuccessfully to introduce an amber codon in the 
middle of my gene of interest in a standard pET vector. I've tried using 
several methods including the Chang et al. double pcr protocol and 
commercial kits such as Stratagene's ex-cite mutagenesis to no avail.  I'm 
changing two ntds and this seems like it should  be very simple. Has anyone 
else tried a nice mutagenesis protocol with decent results. Thanks.